Currently, many so-called head forming and finishing apparatuses are known that carry out flaring, widening, narrowing and other similar head forming and finishing or modifying operations on the heads of pipes.
These head forming and finishing apparatuses basically include a clamp for grabbing the pipe near the head thereof to be worked, and means for driving of a punch tool, mobile in a direction axial to the pipe held by the clamp.
The clamp includes a stationary jaw, supported by the apparatus base, and a mobile jaw moved vertically in such a manner as to be closed on the stationary jaw; the mobile jaw is fastened to a cross-piece displaced, via a couple of lateral vertical connecting rods, by an oil-pressure operated cylinder situated under the working surface.
The traditional head forming and finishing apparatuses have a very bulky structure and are little functional, particularly as the resistance to the stresses is concerned.
In fact, these apparatuses are equipped with very big motors, have long working cycles, with a remarkable energy consumption, and their tool set-up time is long, as well.
Document U.S. Pat. No. 3,411,338 discloses a tube flaring apparatus comprising a support flame and a clamp, operated in a horizontal direction suitable for gripping a pipe in proximity of a head to be worked. The clamp comprises a stationary jaw and a mobile jaw, suitable for operating a tool along a direction axial with respect to the pipe.
The above apparatus suffers for some drawbacks: the support frame is made of several members, which are fixed together by screws, and which have to be made by separate castings; one more tool supporting member is fixed separately from the support frame, and has to be precisely setup. Moreover, the tube head is gripped by the clamp jaws by means of a two-component female die, which is screwed to said jaws. Finally, the tool area and the clamp jaws area not easily accessible and visually controllable by an operator. This makes the apparatus settings quite long and complex.